Impact of Foliar Application of Systemic Fungicides on Yield Attributes and ACI Against Stripe Rust of Wheat

Wheat is a vital global cereal crop, but its productivity and nutritional quality are severely threatened by stripe rust, a devastating fungal disease caused by <i>Puccinia striiformis f. sp. tritici</i>. When genetic resistance in cultivars fails, fungicide application is critical for protecting yields. A study conducted at Khalsa College Amritsar (2022-24) evaluated the efficacy of various fungicides against stripe rust using a Randomized Block Design. Treatments were compared to a control (cultivar PBW-343) based on disease severity, the Average Coefficient of Infection (ACI), and yield parameters including grain yield and 1000-grain weight. Under artificial inoculation, Nativo 75 WG (trifloxystrobin + tebuconazole) applied twice at 15-day intervals recorded the highest grain yield (49.41 q/ha) and 1000-grain weight (43.79 g), increasing yield by 60.95% over control. Custodia, Fusion Top, and Tilt followed, while Opera (pyraclostrobin + epoxiconazole) showed the lowest efficacy (45.68 q/ha, 41.17 g). Nativo also had the lowest ACI (1.6%), compared to the control (54.34%). Other treatments-Custodia (2.4%), Fusion Top (4.65%), Tilt (8.4%), and Opera (11.6%) were statistically superior to control. Systemic fungicides like Custodia, Nativo, Tilt, Opera, and Fusion Top, with diverse modes of action (e.g., DMIs, QoIs), effectively suppressed the disease. These findings highlight their role in managing stripe rust and safeguarding wheat productivity.